Section 5.1
Scientific Notation and Units
Objectives
1. To show how very large or very small numbers can be
expressed in scientific notation
2. To learn the English, metric, and SI systems of
measurement
3. To use the metric system to measure length, volume
and mass
Section 5.1
Scientific Notation and Units
Measurement
• A quantitative observation
• Consists of 2 parts
– Number
– Unit – tells the scale being used
Section 5.1
Scientific Notation and Units
A. Scientific Notation
• Very large or very small numbers can be expressed using
scientific notation
– The number is written as a number between 1 and 10
multiplied by 10 raised to a power.
– The power of 10 depends on:
• The number of places the decimal point is moved.
• The direction the decimal point is moved.
Left  Positive exponent
Right  Negative exponent
Section 5.1
Scientific Notation and Units
A. Scientific Notation
• Representing Large Numbers
• Representing Small Numbers
0.000167 To obtain a number between 1 and 10 we must
move the decimal point.
0.000167 = 1.67 10-4
Section 5.1
Scientific Notation and Units
B. Units
• Units provide a scale on which to represent the results of a
measurement.
Section 5.1
Scientific Notation and Units
B. Units
• There are 3 commonly used unit systems.
– English (used in the United States)
– Metric (uses prefixes to change the size of the unit)
– SI (uses prefixes to change the size of the unit)
Section 5.1
Scientific Notation and Units
C. Measurements of Length, Volume and Mass
• Length
– Fundamental unit is meter
– 1 meter = 39.37 inches
• Comparing English and metric systems
Section 5.1
Scientific Notation and Units
C. Measurements of Length, Volume and Mass
Section 5.1
Scientific Notation and Units
C. Measurements of Length, Volume and Mass
• Volume
– Amount of 3-D space occupied by a substance
– Fundamental unit is meter3 (m3)
Section 5.1
Scientific Notation and Units
C. Measurements of Length, Volume and Mass
• Mass
– Quantity of matter in an object
– Fundamental unit is kilogram
Section 5.1
Scientific Notation and Units
C. Measurements of Length, Volume and Mass